Actually this is not the mortar blowing up! it's a tank shell hitting the guy from a mile away. I saw the full video on some military movie site long ago. Sadly i cant remember what the site is called. But anyhow the guy manage to fire 3 mortars before some radar beacon or some **** detects his position and then the tank (proberly an Abrams) fire a shell in that direction and BAM! big explosion :P